title: Comparison of CAP88 PC Ver. 3.0 and MAXDOSE dose assessment models involving co-located stack releases at the Savannah River site.
abstract: The Savannah River National Laboratory's Environmental Dosimetry Group performs dosimetry assessments for Savannah River Site (SRS) radionuclide air emissions utilizing the Clean Air Act Assessment Package-1988 (CAP88) code (CAP88 PC Ver. 3.0) and the MAXDOSE-SR Ver. 2011 code, which is an SRS-specific version of the Nuclear Regulatory Commission's MAXIGASP code. CAP88 PC and MAXDOSE-SR are used at SRS for demonstrating compliance with Environmental Protection Agency dose standards for radionuclide emissions to the atmosphere and Department of Energy Order 458.1 dose standards, respectively. During a routine comparison of these two assessment models, it was discovered that CAP88 PC Ver. 3.0 was not producing the expected results when using multiple co-located stacks in a single run. Specifically, if the stack heights are considered separately, the results for several radionuclides (but not all) differ from the combined run [i.e., 1 + 2 does not equal (1+2)]. Additionally, when two or more stack heights are considered in a run, the results depend on the order of the selected stack heights. For example, for a two stack-height run of 0 meter and 61 m input produces different results from a 61 m and 0 m input run. This study presents a comparison of CAP88 PC Ver. 3.0 and MAXDOSE-SR Ver. 2011 based on SRS input data and on two-stack release scenarios. The selected radionuclides for this study included gases/vapors (H, C, Kr, and I) and particulates (Sr, Cs, Pu, and Am) commonly encountered at SRS.
authors.affiliation: Savannah River National Laboratory, Aiken, SC 29808, USA. eduardo.farfan@srnl.doe.gov
authors.forename: Eduardo
authors.initials: E
authors.lastname: Farfán
authors.forename: G Timothy
authors.initials: GT
authors.lastname: Jannik
authors.forename: Patricia
authors.initials: P
authors.lastname: Lee
authors.forename: Aaron
authors.initials: A
authors.lastname: Powell
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis*; D004784:Environmental Monitoring / Q000331:legislation & jurisprudence / Q000379:methods / Q000706:statistics & numerical data; D009657:North Carolina; D009688:Nuclear Reactors / Q000331:legislation & jurisprudence / Q000592:standards; D011868:Radioisotopes / Q000032:analysis; D012984:Software / Q000592:standards; D014481:United States; D014484:United States Environmental Protection Agency
chemical_list: D000396:Air Pollutants, Radioactive; D011868:Radioisotopes